Nancy, I agree this gadget would be a value-add for a dishwasher. How did the magnet work out? In my house, my kids (teenagers now) would forget to flip the magnet. I would end up washing the same dishes two or three times. I just know it.
The build instructions explain that a 4.65 minute timer is used. The assumption is that it takes about that long to unload the DW. If you just open to grab a cup, the timer won't run long enough to set the red LED.
This is actually a pretty good and patentable project.
Kevin, according to the instructions provided, the system doesn't know directly if you have taken some or all of the clean dishes out. It has a timer programmed such that if the door is 4.65 minutes in the horizontal position, the dishwasher has been fully unloaded, and less time indicates that only a few dishes have been removed. You can program the system to a different duration, if desired.
Those are really valid things when you have responsible people that utilize the dishes. Try telling that to a 2 year old, a 6 year old and an autistic adult that works on the level of about 4 years old. Unfortunately that is not real life so you try and find the solutions that will make life easier. Hey which is the reason we are engineers in the first place...imagine that!
The vision system is the operator. The first one to the dish washer empties so it's ready for the next dirty item. No excuses.
What I would like to see is a condensing unit added to dish washers to condense the steam and allow it to be drained with the other water. Thus, when the "I'm done" light comes on and you open the door you don't get a blast of steam on your glasses and add humidity to your house, especially in the summer when you're paying the air conditioner to remove heat and humidity. It would also eliminate the water that has re-condensed into the depressions in cups, etc. Seems lke a compressor, agitation fan, and a condensing coil that would fit in your hand would do the job. Then when the "I'm done" light comes on it would indicate the humidity is gone the dishes are safe to transport . . .Simple. Still the first one to need something from the dish washer empties it.
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